(1) Field of the Invention
This invention relates to the dyeing of fabrics.
More specifically, this invention relates to the dyeing of cotton and cotton blends in glycol and glycol ether solvents containing suitable dyestuffs such as direct, sulfur, and disperse dyestuffs.
(2) Description of the Prior Art
The most common solvent for dyeing cotton textiles is water because the solvent provides good solubility of the dyestuffs and contributes to fiber swelling to allow the dye to penetrate the fiber. Chlorinated solvents such as 1,1,1-trichloroethane, trichloroethylene, and perchloroethylene have been used for preparation, finishing, and dyeing of textiles. The major disadvantage of these solvents for dyeing textiles is that polar dyestuffs are not readily soluble in them. Glycol solvents, such as ethylene glycol and diethylene glycol, have been used for dyeing polyamide and polyester textiles. British Pat. No. 760,041 teaches the use of solvents such as ethylene glycol and diethylene glycol for dyeing textile fibers with suitable dyestuffs at temperatures as high as 188.degree. C. for eight to ten seconds. However, these solvents are very poor for dyeing cotton.
Pittman et al, U.S. Pat. No. 4,056,354, has demonstrated that natural fibers, such as wool, can be dyed in ethylene glycol at about 150.degree. C. for 30 seconds or less. Blends of wool and synthetic fibers can also be effectively cross-dyed by using acid dyes and suitable synthetic dyes in the same bath.